The PCIe-TCR card references time code sources including SMPTE, EBU and IRIG-B. This bus-level timing module provides millisecond accuracy to Windows applications; microsecond accuracy is achievable through API development. Both balanced and unbalanced time code inputs are supported. Whenever a time code source is not available or power is lost, the PCIe-TCR will generate its own time from an on-board oscillator. The high-stability oscillator (OCXO) option increases holdover accuracy to ±250ms/year.